Qualitative and quantitative preservation of the fine structure of absorptive cells in cultured biopsies of human small-intestine.

The fine structure of the absorptive cells in human small-intestinal biopsies cultured for 6, 24, and 48 h was analyzed qualitatively and quantitatively. The findings show generally good preservation of the cultured absorptive cells and a normal distribution, size, and relative volume of their cell organelles, but there was a systematic decrease in the apical cell surface and an increase in the number of apical vesicles and tubules after culturing. Since the apical vesicles and tubules are thought to have a function in the transport of cell-coat material from the Golgi apparatus to the cell surface, these findings raise the question of whether a delayed transport or extrusion of cell surface material occurs. The diminished relative volume of the mitochondria and the increased signs of autophagy in some poorly preserved absorptive cells, are assumed to be an adaption to less favourable culture conditions.